Starting next week, 50 sensors will be fitted into parking bays in Westminster each day. Photograph: City of Westminster

The scramble for small change at the parking meter could soon be a thing of the past in central London after the City of Westminster council expanded a "smart" parking trial.

The City is looking into the possibility of creating a "cashless parking scheme", the council's parking services development manager Kieran Fitsall told the Guardian.

"We think it would be easier if you could drive up, park in a space, and the sensor (fitted into a parking bay) notes that you are a registered user," Fitsall said.

As the council has not drawn up any specific plans, there is no information on how the scheme would work exactly.

Illustration: Siraj Datoo

One suggestion is that commuters could apply for a card that allows them to prepay for parking. Once parked, the sensor in the parking bay would record the time and duration of the stay. Users could opt to automatically update their balance in the same way as Transport for London's Oyster card is used in the capital.

Alternatively, the system might be more similar to the auto-pay feature for the congestion charge, where commuters are automatically charged at the end of the month.

This would be a great change from the current system, where commuters have to either pay for parking using their phone via a call, a text, or by using an app – or they can pay for a ticket at a parking machine.

The card itself would need to contain a radio-frequency identification (RFID) chip, which would enable basic information such as the user's account number, linked to their car registration, to be shared wirelessly with the sensor in the parking bay.

Although the council have known about the future benefits of sensors – they asked about possible use cases when they went to tender for the sensors – this is the first time the council have acknowledged they are seriously considering a cashless scheme.

But the council is unlikely to implement the scheme within the next 18 months, Fitsall admitted.

Parking-bay sensors

After a successful testing period that took place for 18 months on five roads including Savile Row and Jermyn Street, the council has signed a contract worth almost £890,000 for Smart Park to fit 10,000 sensors into its parking bays across the city. 3,000 sensors will be initially fitted by March and, if the first phase is deemed successful, a further 7,000 sensors will be embedded into parking bays in Westminster.

Starting next week, 50 sensors will be fitted into parking bays each day. The sensors note when and where someone has parked and send the data back to the council, which is also working with app developers Parkopedia to help users find the nearest available space.

A parking sensor in a Westminster parking bay. Photograph: City of Westminster

Smaller, newer model

Sensors already installed for the initial trial will be replaced by a newer model that is smaller and it contains an RFID chip, which is currently embedded within Oyster cards.

A new cashless system means commuters would never have to get out of their car, instead being automatically charged depending on how long they park.

During the testing period, the councils were able to aggregate a wealth of data about parking demand, intensity, and the schedules of drivers. For example, they were able to note which roads commuters were most likely to go to in their search for parking. The council hopes the scheme will help people spend more time in shops and less time looking for parking.

Traffic wardens can see how long someone has parked – through a smartphone app – but are not using it to fine those who overstay the limit, according to Andrew Busby, national account manager at Smart Parking, who manufacture the sensors.

A longer-term prospect, should the sensors be so successful that they are implemented across London, is that the technology could be streamlined into a separate "City pass" especially for London's drivers. Alternatively, it could be linked to the government-backed MultiPass, announced last year, which could be used on trains, buses, the tube and even to catch flights.

TfL said in November 2013 that they were planning to phase out Oyster cards and would instead allow commuters to pay using their contactless bank cards. Although commuters can already pay for journeys on London's buses using contactless cards, once the system is fully implemented, users will be able to use their card like they do their Oyster, with a cap on daily limits to be introduced.

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